Succession A2 Flashcards
Define succession.
The process by which an ecosystem changes over time in a series of stages.
What is a climax community?
The final stage in an ecological succession. Stale community, changes very little.
Hostility
Abiotic factors are unfavourable, few species adapted to survive in these conditions. (diversity low)
Abiotic environment.
non-living parts of environment i.e. temperature, soil mineral ion concentration, salt concentration, amount of water retention.
Diversity.
Relationship between the number of individual organisms and the number of species within a community.
Succession occurs in natural ecosystems.
Describe and explain how succession occurs.
(5)
- colonisation by pioneer species
- change in environment / eg. increase in nutrients
- enables other species to colonise/survive
- change in diversity/biodiversity
- stability increases / less hostile environment
- climax community
What occurs as a result of deflected succession?
- climax community is prevented from establishing
- such conditions on a community is known as plagioclimax
What are pioneer species?
The organisms that first colonise an area. Eg. marram grass in sand dune ecosystems
What is a sere and a seral community?
a complete succession from pioneer community to climax community, and a seral stage is a particular stage in this succession with its own distinctive community of organisms.
Give 4 reasons why we should conserve wildlife and why.
Ecological - protect wildlife/food chains, prevent extinction, global warming, maintain biodiversity
Economic - resources (food, wood, medicine)
Ethical - not harming species
Social - human physical + mental health
Give 6 conservation methods.
Protected areas - laws, permits, national parks, tagging animals
Captive breeding - reintroduce to wild
Fishing quotas
A-forestation - replanting trees
Seed banks - conserve rare plants
Manage succession to preserve ecosystem
Name and explain 7 conservation conflicts.
- Coppicing trees - can bring disease back
- Limited area for building infrastructure
- Quotas have an economic impact
- Businesses want resources (palm oil etc)
- Reduced area for farming + agriculture/deforestation for materials
- May increase tourism (national parks) - negative effect on environment
- Can reintroduce disease in animals when reintroduces back into new area.
Explain what the copper cycle/sink is and benefits and drawbacks.
- chop tree but leave part of trunk without damaging roots
- tree grows back over time + can e cut down again
- increases biodiversity when trunk is short as more light attracting new species
- however can bring disease back
What adaptations do pioneer species tend to have? (5)
- A tolerance to extreme conditions
- The ability to fix nitrogen from the air
- Ability to photosynthesis light.
- Can easily disperse seeds across vast distances
- Rapid germination of seeds